Looking to dye your lovely locks, but without the toxic chemicals? Well, you’re in luck because you could be dying your hair with gold someday. Though a couple of scientists in New Zealand were able to successfully dye lamb’s wool with gold, Dr. Philippe Walter at Université Pierre et Marie Curie-CNRS and his colleagues were interested in trying out gold nanotechnology to dye hair. It’s known that the Romans and Greeks used to dye their hair with lead, so Dr. Walter figured gold would have similar effects. They carried out the test on a couple of white hairs by soaking them in gold particles. After a day, the hairs turned yellow then a little over two weeks later, the hairs were permanently a dark brown — even after several washes.